This 10-minute timer was found in the July 1994 Radio Electronics magazine. The relay must be sensitive to the supply voltage used. The capacitors determine time ranges.
LTC7841 PolyPhase® Synchronized Boost Controllers Mouser Announces Analog Devices LTC7841...
This interesting circuit is for controlling a small robot that searches for a light source. The...
This VCO or Voltage Controlled Oscillator was found in a Popular Electronics from 1991 but can be...